My invention involves a better dispensing system using a cartridge and plunger formed so that the plunger is locked onto and sealed to the rear end of the cartridge. It was developed especially for a large cartridge having a diameter of about five inches and a dispensing gun having a powered pusher to drive the plunger forward during dispensing. There is no reason why my invention could not also apply to smaller cartridges and plungers that are not necessarily advanced by power driven pushers.
My invention aims at simplicity, economy, and effectiveness in a cartridge and plunger interrelationship that both locks and seals. A locking arrangement connects the plunger securely to the rear end of the cartridge so that it will not come loose or be backed out by contents expansion, and the plunger also serves as a secure seal closing the rear end of the cartridge tightly enough to protect the contents. The plunger keeps the dispensing gun pusher clean during operation and allows dispensing simply by driving the plunger forward.